Re the hand luggage, pax will always try to take it off with them.
people panic and do not behave rational. Years ago I happened to be in an office when the house (3 floors) caught fire somewhere 'up there' (a flat on the top floor, as it appeared later). Everyone grabbed the
papers on the desks (me, too, as that's what was going on around me) and run out. How's that explainable? It's not even like walking out of the plane with 2 hands in your pocket, to a foreign country for many.